Evidence for Orientational Order in Nanothreads Derived from Thiophene
Journal
Journal of Physical Chemistry Letters
Journal Volume
10
Journal Issue
22
Start Page
7164
End Page
7171
ISSN
19487185
Date Issued
2019
Author(s)
Biswas, Arani
Ward, Matthew D.
Wang, Tao
Zhu, Li
Badding, John V.
Crespi, Vincent H.
Strobel, Timothy A.
Abstract
Nanothreads are one-dimensional sp3 hydrocarbons that pack within pseudohexagonal crystalline lattices. They are believed to lack long-range order along the thread axis and also lack interthread registry. Here we investigate the phase behavior of thiophene up to 35 GPa and establish a pressure-induced phase transition sequence that mirrors previous observations in lowerature studies. Slow compression to 35 GPa results in the formation of a recoverable saturated product with a 2D monoclinic diffraction pattern along (0001) that agrees closely with atomistic simulations for single crystals of thiophene-derived nanothreads. Paradoxically, this lower-symmetry packing signals a higher degree of structural order since it must arise from constituents with a consistent azimuthal orientation about their shared axis. The simplicity of thiophene reaction pathways (with only four carbon atoms per ring) apparently yields the first nanothreads with orientational order, a striking outcome considering that a single point defect in a 1D system can disrupt long-range structural order. © 2019 American Chemical Society.
Publisher
American Chemical Society
Type
journal article